Polyphenylene ether (hereinafter, also referred to as “PPE”) resin compositions based on polyphenylene ether resins have features such as heat resistance, electrical properties, dimensional stability, impact resistance, and low specific gravity. Moreover, since it is possible to provide polyphenylene ether resin compositions with flame retardance without the need to use halogen-containing compounds and antimony compounds that have a high environmental burden, polyphenylene ether resin compositions are used in a wide range of applications such as various electric and electronic components, office equipment components, automotive components, building materials, and other exterior materials and industrial goods.
In recent years, progress toward more compact and higher performance components has resulted in demand for favorable long-term properties in addition to short-term properties. Consequently, there is demand for a polyphenylene ether resin composition to maintain mechanical strength and flame retardance even upon long-term exposure to a high-temperature environment.
Examples of methods for increasing thermal stability of polyphenylene ethers that have been developed up until the present time include a technique of including a specific hydrogenated block copolymer and a specific flame retardant in a specific composition and adopting a specific production method (refer to PTL 1), and a technique of polyphenylene ether terminal stabilization through addition of a vinyl compound (refer to PTL 2).